// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_BROWSER_SHUTDOWN_PROFILE_DUMPER_H_
#define CONTENT_BROWSER_BROWSER_SHUTDOWN_PROFILE_DUMPER_H_

#include <stddef.h>

#include <string>

#include "base/files/file_path.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/ref_counted_memory.h"
#include "content/common/content_export.h"

namespace base {
class FilePath;
class WaitableEvent;
}

namespace content {

// This class is intended to dump the tracing results of the shutdown process
// to a file before the browser process exits.
// It will save the file either into the command line passed
// "--trace-shutdown-file=<name>" parameter - or - to "chrometrace.log" in the
// current directory.
// Use the class with a scoped_ptr to get files written in the destructor.
// Note that we cannot use the asynchronous file writer since the
// |SequencedWorkerPool| will get killed in the shutdown process.
class BrowserShutdownProfileDumper {
public:
    explicit BrowserShutdownProfileDumper(const base::FilePath& dump_file_name);

    ~BrowserShutdownProfileDumper();

    // Returns the file name where we should save the shutdown trace dump to.
    static base::FilePath GetShutdownProfileFileName();

private:
    // Writes all traces which happened to disk.
    void WriteTracesToDisc();

    void EndTraceAndFlush(base::WaitableEvent* flush_complete_event);

    // The callback for the |TraceLog::Flush| function. It saves all traces to
    // disc.
    void WriteTraceDataCollected(
        base::WaitableEvent* flush_complete_event,
        const scoped_refptr<base::RefCountedString>& events_str,
        bool has_more_events);

    // Returns true if the dump file is valid.
    bool IsFileValid();

    // Writes a string to the dump file.
    void WriteString(const std::string& string);

    // Write a buffer to the dump file.
    void WriteChars(const char* chars, size_t size);

    // Closes the dump file.
    void CloseFile();

    // The name of the dump file.
    const base::FilePath dump_file_name_;

    // The number of blocks we have already written.
    int blocks_;
    // For dumping the content to disc.
    FILE* dump_file_;

    DISALLOW_COPY_AND_ASSIGN(BrowserShutdownProfileDumper);
};

} // namespace content

#endif // CONTENT_BROWSER_BROWSER_SHUTDOWN_PROFILE_DUMPER_H_
